Some microorganisms (such as molds, fungi or bacteria) grow on crops (including grains) and forages and produce toxins known as mycotoxins. These mycotoxins can be poisonous, mutagenic, teratogenic or carcinogenic when consumed by humans or livestock. Feeds that contain mycotoxins reduce animal productivity and may cause disease or even death.
Mycotoxins are usually found in temperate regions. The microorganisms often propagate in agricultural plants whenever environmental conditional are favorable. Such conditions include cool damp summers, late wet harvests and poor storage after harvest. Where mold growth has occurred it is likely that mycotoxins have been produced.
Mycotoxins can remain in food and feed long after the microorganism that produced them has died. Therefore toxins can be present at potentially dangerous levels in products that are not visibly moldy.
In any given year approximately 20% of all grains harvested become infected with mycotoxins. This infected grain has little value for either human consumption or animal feed. The mycotoxins can be poisonous, mutagenic, teratogenic or carcinogenic to both humans and animals. Mycotoxins can also lower the nutritional value of feed by changing the vitamin and amino acid content. This reduces the energy derived from the feed, which leads to lower feed efficiency. Losses of freshness and palatability results in feed rejection and lower weight gain. Reproduction difficulties of farm animals caused by mycotoxins can also be costly.
There has not previously been a satisfactory method for remedying the problem of mycotoxin infection. Infected crops must be discounted or discarded. Since no acceptable method of dealing with mycotoxins exists, the United States Food and Drug Administration consider mycotoxin infection to be a serious financial and health problem.